Many methods and apparatus for accessing subcutaneous structures (e.g., vessels, such as veins and arteries, or other structures) are known. One common need for subcutaneous access involves intravenous insertion or extraction of fluids, medications, or the like when administering medical treatment to a patient. Subcutaneous access may be needed in, for example, the following medical facilities and departments: emergency, labor and delivery, laboratory, oncology, operating room, intensive care unit, pediatrics, and pediatric and neonatal intensive care unit.
For example, in emergencies, every second counts, and finding a vein in a critically injured or ill patient can be highly difficult and time-consuming when delivery of medications, fluids, and/or nutrients is most critical. In labor and delivery, an intravenous access device is often immediately placed in a patient during the admitting process for hydration or to introduce medication. Pregnant women may have, for example, pregnancy-induced hypertension, vaso-constricted veins, and/or edema—all of which contribute to challenging venipuncture. There are many reasons that lab work is needed during the course of one's life, at times with varying states of health that can greatly affect the ease of accessing a patient's subcutaneous structures. In oncology, frequent infusion therapies often make a patient's peripheral vasculature fragile and limited. In the operating room, unsuccessful attempts at peripheral intravenous access delay many operations. In the intensive care unit, there are many factors that can change a critical patient's status in an instant. When peripheral access cannot be attained and a central venous catheter must be placed, a patient's risk for infection—particularly risky bacterial staph infections—goes up significantly. In pediatrics, children pose a particular challenge for venipuncture due to their relatively small vessels and limited access points. Often adding to these challenges are the fears of the child and the great anxiety of their parents. When the patient is in the highly sensitive pediatric and neonatal intensive care unit, the situation can be even more challenging.
In the administration of medical care to a patient requiring subcutaneous access, especially in an emergency situation, such as that encountered by a physician, nurse, emergency medical technician (EMT), or other health care provider, or in the treatment of an accident victim at the scene of the accident, or in the treatment of wounded on a battlefield by a medic, environmental conditions under which medical care is administered may be adverse. These conditions include those associated with nighttime lighting conditions. It is well settled that expeditious administration of medical care to a victim improves the prospects of the victim's recovery. For example, the life of a soldier wounded on the battlefield may depend on the immediate intravenous administration of blood plasma, other lost body fluids, or medications. Similar immediate procedures by a health care provider may be required in order to treat a victim at the scene of an accident. Further, during transport of a victim to a hospital or similar medical care facility, administration of medical procedures may be necessary, but difficult to perform, under poor lighting conditions or under other adverse conditions (e.g., those associated with torn clothing, bleeding, or other circumstances). Shock may have caused veins of a victim to partially collapse, or the patient may have veins that are difficult to find (such as in the treatment of infants or obese persons), which further complicates procedures for accessing the veins.
Having subcutaneous fluid extracted (e.g., having blood drawn) or starting an intravenous access can be an uncomfortable, or even painful, experience for patients. In addition to a fear of needles, many patients must unfortunately endure multiple needle sticks when a nurse or technician cannot easily find an appropriate access point. Not surprisingly, even with adequate environmental conditions, finding a subcutaneous structure such as a vein is not always an easy task. Even the most seasoned health care providers may have to stick a patient multiple times before successfully locating a vein. A number of factors can make it difficult to find a patient's veins, including: age, frequent (or lengthy) infusion therapies, multiple disease states, dehydration, hypertension, size and fragility of blood vessels, skin tone, and presence of edema or fatty tissue. Thus, ways to facilitate ease and comfort of subcutaneous access are desirable.
U.S. Pat. No. 6,230,046 describes a system and method for enhancing the visualization of veins, arteries, or other subcutaneous natural or foreign structures in the body and for facilitating intravenous insertion or extraction of fluids, medications, or the like in the administration of medical treatment to a patient. The system and method include a light source of selected wavelength(s) for illuminating or trans-illuminating a selected portion of the body and a low-level light detector and suitable filters for generating an image of the illuminated body portion.
See also U.S. Patent Publication No. 2004/0215081. Illustrated therein is an apparatus and method for image extravasation or infiltration in a forearm. The forearm is placed proximate a near infrared light source, between the light source and a detector.
Still further, U.S. Patent Publication No. 2007/0032721 describes a disposable light source patch for enhanced visualization of subcutaneous structures. The patches therein are stated to be adhesively attached to a body portion of a patient and suitable for use in conjunction with certain systems and methods, such as those described in U.S. Pat. No. 6,230,046.
Luminetx Corporation (Memphis, Tenn.) markets a product for location of subcutaneous veins and projection of real-time images of their location onto the surface of the skin. The product is commercially available under the VEINVIEWER trade designation.
Despite advances in imaging, especially for visualization of subcutaneous structures in a patient's body, current systems tend to be cumbersome and inefficient. For example, in known procedures for visualization of subcutaneous structures, proper support of a light source in order to accurately direct the light onto a body portion of interest may be an awkward procedure for the health care provider when treating a patient. Moreover, current devices distinctly comprise light source(s) and support structure(s) that are essentially separate components that may be used together but are not intrinsically combined as an optimized device and as such have significant light losses and inefficiencies. There is, therefore, a continued need for improved devices for imaging processes associated with subcutaneous access. Further, there is a need for subcutaneous access devices that are portable and capable of efficient use in a variety of environments.